A044200 Numbers n such that string 1,5 occurs in the base 8 representation of n but not of n-1.

13, 77, 104, 141, 205, 269, 333, 397, 461, 525, 589, 616, 653, 717, 781, 832, 909, 973, 1037, 1101, 1128, 1165, 1229, 1293, 1357, 1421, 1485, 1549, 1613, 1640, 1677, 1741, 1805, 1869, 1933, 1997, 2061, 2125, 2152, 2189, 2253, 2317, 2381, 2445, 2509, 2573

Offset

1,1

Links

Table of n, a(n) for n=1..46.

Mathematica

f[n_] := Length[StringPosition[ToString[FromDigits[IntegerDigits[n, 8]]], "15", 1]]; a = Select[Table[n, {n, 10000}], f[#] > 0 && f[# - 1] == 0 &] (* Vladimir Joseph Stephan Orlovsky, Jul 16 2011 *)
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 8], {1, 5}]>0, 1, 0], {n, 2600}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 16 2017 *)

Crossrefs

Cf. A044581.

Sequence in context: A269071 A283539 A060717 * A329109 A044581 A126423

Adjacent sequences: A044197 A044198 A044199 * A044201 A044202 A044203

Keyword

nonn,base

Author

Clark Kimberling

Status

approved